System and method for secure communications between controllers in a vehicle network

A system and method are described for secure communications between controllers in a vehicle network. The system includes multiple controllers associated in a group and configured to communicate with each other, each having an initial controller identification (ID) number and configured to communicate with a gateway controller. Each controller in the group is configured to calculate an updated controller ID number and transmit the updated controller ID to the gateway controller in a secure fashion, and the gateway controller is configured to authenticate and transmit the updated controller ID of each controller in the group to all the controllers in the group in a secure fashion. Each controller in the group is further configured to include its updated controller ID in network messages transmitted to other controllers in the group, and to authenticate other controllers in the group based on the updated controller IDs in network messages from other controllers.